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Related papers: Rationality of certain triangle tilings

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We show how to determine if a given simple rectilinear polygon can be tiled with rectangles, each having an integer side.

Combinatorics · Mathematics 2009-09-25 Richard Kenyon

Let ABC be a triangle with a,b,and c being its three sidelengths. In a 1976 article by Wynne William Wilson in the Mathematical Gazette(see reference[2]), the author showed that angleB is twice angleA, if and only if b^2=a(a+c). We offer…

General Mathematics · Mathematics 2012-08-03 Konstantine Zelator

For a triangle $\Delta$, let (P) denote the problem of the existence of points in the plane of $\Delta$, that are at rational distance to the 3 vertices of $\Delta$. Answer to (P) is known to be positive in the following situation: $\Delta$…

Number Theory · Mathematics 2013-01-29 Roy Barbara , Antoine Karam

We introduce a new family of nonperiodic tilings, based on a substitution rule that generalizes the pinwheel tiling of Conway and Radin. In each tiling the tiles are similar to a single triangular prototile. In a countable number of cases,…

Group Theory · Mathematics 2018-07-10 Lorenzo Sadun

We prove that is a measurable domain tiles R or R^2 by translations, and if it is "close enough" to a line segment or a square respectively, then it admits a lattice tiling. We also prove a similar result for spectral sets in dimension 1,…

Classical Analysis and ODEs · Mathematics 2016-09-07 Mihail N. Kolountzakis , Izabella Laba

All edge-to-edge tilings of the sphere by congruent regular triangles and congruent rhombi are classified as: (1) a $1$-parameter family of protosets each admitting a unique $(2a^3,3a^4)$-tiling like a triangular prism; (2) a $1$-parameter…

Combinatorics · Mathematics 2023-11-27 Qi Yuan , Erxiao Wang

There exist tilings of the plane with pairwise noncongruent triangles of equal area and bounded perimeter. Analogously, there exist tilings with triangles of equal perimeter, the areas of which are bounded from below by a positive constant.…

Combinatorics · Mathematics 2018-02-07 Andrey Kupavskii , János Pach , Gábor Tardos

Richard Guy asked the following question: can we find a triangle with rational sides, medians, and area? Such a triangle is called a \emph{perfect triangle} and no example has been found to date. It is widely believed that such a triangle…

Combinatorics · Mathematics 2019-10-16 Mehdi Makhul

We deal with unweighted and weighted enumerations of lozenge tilings of a hexagon with side lengths $a,b+m,c,a+m,b,c+m$, where an equilateral triangle of side length $m$ has been removed from the center. We give closed formulas for the…

Combinatorics · Mathematics 2007-05-23 Mihai Ciucu , Theresia Eisenkölbl , C. Krattenthaler , D. Zare

The work of Mills, Robbins, and Rumsey on cyclically symmetric plane partitions yields a simple product formula for the number of lozenge tilings of a regular hexagon, which are invariant under roation by $120^{\circ}$. In this paper we…

Combinatorics · Mathematics 2017-05-04 Tri Lai , Ranjan Rohatgi

We study tilings of the plane that combine strong properties of different nature: combinatorial and algorithmic. We prove existence of a tile set that accepts only quasiperiodic and non-recursive tilings. Our construction is based on the…

Discrete Mathematics · Computer Science 2015-06-15 Bruno Durand , Andrei Romashchenko

Convex hexagons that can tile the plane have been classified into three types. For the generic cases (not necessarily convex) of the three types and two other special cases, we classify tilings of the plane under the assumption that all…

Combinatorics · Mathematics 2024-05-09 Xinlu Yu , Erxiao Wang , Min Yan

We know that tilesets that can tile the plane always admit a quasi-periodic tiling [4, 8], yet they hold many uncomputable properties [3, 11, 21, 25]. The quasi-periodicity function is one way to measure the regularity of a quasi-periodic…

Cellular Automata and Lattice Gases · Physics 2010-12-07 Alexis Ballier , Emmanuel Jeandel

We provide a complete description of the edge-to-edge tilings with a regular triangle and a shield-shaped hexagon with no right angle. The case of a hexagon with a right angle is also briefly discussed.

Combinatorics · Mathematics 2023-05-30 Thomas Fernique , Olga Mikhailovna Sizova

We give a formula for counting the triangles in a picture consisting of the three sides of a triangle and some cevians. This lets us prove statements that are claimed without proof in the Online Encyclopedia of Integer Sequences and some…

Combinatorics · Mathematics 2024-10-28 Jim Propp , Adam Propp-Gubin

We call "flippable tilings" of a constant curvature surface a tiling by "black" and "white" faces, so that each edge is adjacent to two black and two white faces (one of each on each side), the black face is forward on the right side and…

Differential Geometry · Mathematics 2014-05-23 Francois Fillastre , Jean-Marc Schlenker

We consider the problem of finding integer triangles with $R/r$ a positive rational, where $R$ and $r$ are the radii of the circumcircle and an excircle, respectively. We show that for general triangles $R/r>1/4$ applies. The equation…

Number Theory · Mathematics 2025-12-18 Lorenz Halbeisen , Norbert Hungerbühler , Arman Shamsi Zargar

We apply Diophantine analysis to classify edge-to-edge tilings of the sphere by congruent almost equilateral quadrilaterals (i.e., edge combination a3b). Parallel to a complete classification by Cheung, Luk and Yan, the method implemented…

Combinatorics · Mathematics 2022-08-05 Ho Man Cheung , Hoi Ping Luk

We study side-lengths of triangles in path metric spaces. We prove that unless such a space X is bounded, or quasi-isometric to line or half-line, every triple of real numbers satisfying the strict triangle inequalities, is realized by the…

Metric Geometry · Mathematics 2014-11-11 Michael Kapovich

Nandakumar asked whether there is a tiling of the plane by pairwise non-congruent triangles of equal area and equal perimeter. Here a weaker result is obtained: there is a tiling of the plane by pairwise non-congruent triangles of equal…

Metric Geometry · Mathematics 2016-03-31 Dirk Frettlöh